Burner



G. W. MCKEE Dea 12, 1933.

BURNER Filed Feb. 6, 1931 u 0 l! I Patented Dec. 12, 1933 UNITED srArEsPATENT o.fI-"F1clf=v-A BURNER Garnet W. McKee, Rockford, Ill.Application February s, 1931. serial No. 513,948

.12 Claims.

The present invention relates to improvements in burners, and hasparticular reference to burners adapted for use with means for producingand supplying an adjustable proportionate mixture of fuel and air, suchfor example as a jet inspirator. Y

Jet inspirators commonly comprise a mixing tube, a chamber communicatingwith the inlet end of the tube and adapted to be supplied with one ofthe fluid constituents of the fuel mixture, and a nome for discharging ajet of the other fluid constituent of the fuel mixture, as the drivingfluid, into the tube to induce a proportionate flow 0f fluid from thechamber into the tube.

In my copending application, Serial No.Y

427,713, filed February 12, 1930, I have shown a jet inspirator of thelow pressure type in which the fuel is the induced fluid. The presentinvention relates to a burner comprising a jet inspirator of the highpressure type in which the fuel is the inducing fluid and atmosphericair is the induced fluid. The fuel and air ratio in the mixture flowingthrough the mixing tube is subject to adjustment by adjusting the areaof the air inlet to -the chamber about the fuel nozzle. to the burnermay be adjusted through the agency of a control valve in the fuel supplyline.

`Various objects of the present invention reside in the provision of anovel gas burner of the high pressure type which has a wide range ofadjustment, which is not likely to back-nre even though the fuelpressure is reduced to minimum,

which may supply the primary fuel mixture without blowing the flame awayfrom the burner tip, and which has a relatively small overall length.

Another important object is to provide a new and improved burner of thehigh pressure type which constitutes part of the 'proportional mixer,

and which is adapted to be positioned closely to the furnace tuyre, sothat the mixture of fuel and air is not mixed intimately or completelywithin the burner tube, and hence is not so likely to result inback-firing as woulda more perfect mixture.

A further object resides in the provision of a burner of the high,pressure type comprising means for supplying one or more small pilotstreams of gas to the burner. tip which gas is availableto supplementvthe gas in the primary mixture to maintain a final mixture of the def'sired proportions, andwhich serves to keep the burner ignited at alltimes.

Further objects and advantages will become apparent as the descriptionproceeds.

\ disclosed, but intend to cover The volume lof fuel mixture suppliedtal fuel directly tothe burner V(Cl. 158-109) In the 'drawing,`Figure 1is a view, partially in section of a burner embodying the features of myinvention.

Fig. 2 is a view of the discharge end of the burner tube taken alongline 2--2 of Fig. 1.

Fig. 3 is a sectional view taken along line 3-3 of Fig. 1.

While the invention is susceptible of various modifications andalternative constructions, I k have shown in the drawing and will hereindescribe in detail the preferred embodiment, but it is to be understoodthat I do not thereby intend to limit the invention to the specific formall modifications and alternative constructions falling within thespirit and scope of the invention as expressed in the appended claims.

Referring more particularly to the drawing, the burner in its' preferredform comprises a burner tube 10 of suitable form. In the present 75instance, theV tube 10 is elongated, and is formed with a straightpassage of which the inlet end is smoothly rounded on a relatively largeradius as indicated at l1, and of which the discharge end is smoothlyrounded on a relatively small radius as indicated at 12.

The burner tube l0 constitutes also the mixing tube of a fuel and airmixer which may be of any suitable form. In the present instance, themixer comprises a casing 13 secured to the inlet 35 end of the tube 10.The casing 13 is formed -internally with a hollow central fitting 14 inspaced relation Ato the tube 10, and connected to a fuel line 15 adaptedto supply fuel, such as gas or oil, from a suitable source under thedesired pressure. A control valve 16 is interposed in the line 15 foradjusting the amount of fuel supplied.

' Opening from the fitting 14 is a restricted orifice or nozzle 17discharging axially into the tube 10.

The rear 'of Athe casing 13 opens about the fit- 95 ting 14 to theatmosphere to define a primary air inlet 18. A shutter 19 adjustablymounted on the casing 13v across the inlet 18 serves as means forregulating the amount of primary air supplied. Preferably, the orifice17 is of such 10o' a size that with the shutter 19 completely open,insufllcient air for complete combustion will be supplied through theinlet 18. It will be evident that the jet of fuel issuing from theorifice 17 will entrain or inject air from the casing 13'in 105 adefinite proportion, and will cause a primary mixture of fuel and air topass through the tube 10 at a high velocity.

To provide means for supplying supplementip, the tube 10 is 110 spacedsecondary air inlet ports 34.

lfurnace wall formed adjacent its outer end with an outer peripheralflange 20 defining an annular shoulder 21, and is formed intermediatethe shoulder and the tip with an elongated peripheral recess 22. Anouter sleeve' 23 is fitted snugly over the tube' 10 and against theshoulder 21,. and preferably is Welded to the latter, thus constitutingthe recess 22 a closed annular fuel chamber. Formed in the outerperiphery of the burner tip in spaced relation are a plurality oflongitudinal pilot ports 24 adapted to discharge fuel from the chamber22 about the mixture issuing from the tube 10. The inner or dischargeend of the sleeve 23 defines a fiat annular face 25 about the ports 24.'Fuel is supplied from the line 15 to the chamber 22 through a branchline 26. The line 26 is located at the burner. side of the valve 16 so'that the supply of gas to the chamber 22 is varied in the same relationas that to the orifice 17. Interposed in the line 2,6 is a pressurereducing means 27 of suitable construction.

Where the burner is intended for use on a furnace and not as a torch, asleeve 28 is mounted in concentric spaced relation about the dischargeend of the'tube 10, and more specifically is formed on its outer endwith an inner peripheral end flange 29 seating against an annularshoulder 30 formed in the sleeve 23. The other end of the sleeve 28 isformed with an outer peripheral flange 31 adapted to be mounted on a 32concentrically -about an opening 33 formed in the latter. 'I'he opening33 in the furnace wall 32 is larger than the outside diameter of thetube 10, and preferably is slightly flared inwardly. Formed in theperipheral wall of the sleeve 28 are a plurality of longitudinal Acylindrical air shutter 35 mounted on the sleeve 28 is formed with airinlet ports 36 corresponding in size and spacing to the ports 34, and isrotatably adjustable against the flange 31 to bring the ports 34 and 36into various degrees of registration so as to control the supply ofsecondary air to the burner tip. In operation, the shutter 19 normallyis left wide open. The valve 16 is opened to supply gas or oil to theorifice 17 and 'at a reduced pressure to the chamber 22. A primary fuelmixture, ,deficient in air, thus is caused to flow at a -high velocitythrough the burner tube 10. Fuel jets which when ignited constitutepilot flames also issue from the ports 24 about the primary stream. Thesecondary air required for complete combustion of the primary stream aswell as of the pilot streams is drawn through the ports 34 and 36 aboutthe burner tip into the furnace opening 33, The pilot ilames actcontinuously to keep the primary stream ignited, which is essentialsince the latter by reason of its high velocity would otherwise tend tobecome'extinguished. By reason of the small curvature at ,12 and thefiat suri roun face 25, the primary fuel stream does not tend to blowout the pilot flames, but on the contrary. tends continuously to` drawthe pilot flames and the secondary air toward itself. Thus.1trilulieiliot llames act constantly to keep the burner It win beevident um the fuel-air raue er the'- flnal mixture may .be made exactlycorrect for complete combustion, or may be varied .over a substantialrange to obtain a reducing flame or an llame as desired. Due tothepartial primary mixing of fuel and air and the complete utilization ofthe velocity pressure, a fast moving but slow burning mixture results.Hence. a flame having very desirable characteristics is obtained, andthe fuel pressure can be reduced considerably below the normal low pointof operation of high pressure burner without the likelihood of backflashing.

I claim as my invention:

1. A burner comprising, in combination, a burner tuyre, a burner tubemounted in operative relation to said tuyre, means for supplying aproportionate gaseous fuel mixture under a high lvelocity tothe inletend of said tube, a fuel supply line connected to said means, a linebranching from said first mentioned line for supplying a restrictedquantity 'of supplemental fuel to the discharge tip of said tube aboutthe periphery thereof, pressure reducing means in said last mentionedline, and adjustable means for supplying secondary air about said tip tosaid mixture and said supplemental fuel.

2. A burner comprising, in combination, a

burner tuyre, a burner tube having a iongitudi nal passage openingtherethrough, a sleeve fitting about said tube and defining an annularspace therewith, a plurality. of spaced ports opening from said spacethrough the tip of said tube to said tuyre, ay casing open to theatmosphere and connected to the inlet end of said tube, a nozzle in saidcasing discharging axially into said tube. valve controlled means forsupplying fuel to said nozzle, and means for supplying supplemental fuelat a reduced pressure from said first mentioned means to said space.

3. A gas burner comprising, in combination, an elongated burner tubehaving a discharge tip at one end, an atmospheric air casing opening tothe other end of said tube, a restricted injector nozzle mounted in saidcasing to discharge axially into said other end of said tube, a gassupply line connected to said nozzle,`means for discharging a.restricted quantity of supplemental gas to said discharge tip about theperiphery thereof, and a line branching from said first mentioned linefor supplying gas to -said means.

4. A burner comprising, in combination, a burner tube having a lstraightlongitudinal passage opening therethrough, the inletend of said passagebeing flared on a relatively large radius and the outlet end of saidpassage 4being flared convexly on a relativelyfsmall radius, a sleevefittingv about said tube and defining an annular space therewith out ofcommunication'withsaid passage, the end of said sleeve defining a fiatannular surface about the outlet end of said passage, a plurality o fperipherally spaced .ports opening from said space about the dischargeend of said tube, means for supplying a mixture of fuel and air to saidtube, and means for supplying supplemental fuel to said space.

,5. A burner comprising, in combination, a burner tube having a straightvlongitudinal passage opening therethrough, the outlet end of saidpassage being flared outwardly on a relatively small radius, a sleevefitting about said tube and defining an annular space therewith, the

vend of said sleevedening a fiat annular surface about the aredvoutletend of said pe. a plurality of peripherally spaced ports. openingfrom said space to said surface about the discharge end of said tube, anannular air space opening about the discharge end of said tube, mean forsupplying a mixturel of fuel and ,air under pressure to said tube, andmeans for supplying fuel to said first mentioned space.

6. A burner ti'rvre. a vburner tube 'smaller in ,diameter thancomprising, in combination, al

said tuyre and disposed in axial alinement there# with, said tube beingformed with a central passage and an annular chamber about said passagehaving a plurality of outletports discharging about the outlet end ofsaid passage into said tuyre, a concentric sleeve mounted inperipherally spaced relation on said tube and about said tuyre andformed with a`plurality of peripherally spaced openings, a shutterrotatably mounted on saidsleeve and formed with a plurality ofperipherally spaced openings adjustable into various degrees -ofregistration with said first mentioned openings, means for supplying aproportionate mixture of fuel and air to said tube and being adjustableto vary the volume of said mixture and to vary the proportion of fueland air in said mixture, and meansfor supplying supplemental fuel tosaid chamber.

. 7. A burner comprising, in combination, a tuyre, a burner tube havinga longitudinal passage opening therethrough, the exterior of said tubebeing recessed peripherally with a shoulder at the discharge tip, asleeve fitting about said burner tube and defining a closed annularspace therewith, a plurality of peripherally spaced ports formed in saidshoulder and opening from said space to said tuyre, a casing connectedtothe inlet end of =said tube. a nozzle in said casing and discharginginto said tube, a valve controlled line for supplying fuel to saidnozzle, means for admitting air to said casing, and a line connectingsaid rst mentioned line to said space.

8. A burner comprising, in combination, a tuyre, a burnertube having alongitudinal passage opening therethrough and discharging to said tuyre,a chamber about said tube, a plurality of spaced ports formed in the tipof said tube and opening `from said chamber to said tuyre, a suctionchamber connected to the inlet endof said tube, a nozzle adapted todischarge into the inlet end of said tube, a line for supplying a fuelunder a high pressure to said nozzle, means forI ,supplying air to saidsuction chamber, and a line branching from said first mentioned line forsupplying a small stream of supplemental fuel to said first mentionedchamber.

9. A gas burner comprising, in combination, an elongated burner tubehaving a discharge tip at one end, a casing connected to and incommunication with the other end of said tube, said casing having anatmospheric air inlet opening, an adjustable shutter for controlling theeffective area of said opening, a restricted injector nozzle mounted insaid casing to discharge axially into said other end of said tube, meansfor `discharging a restrictedquantity of gas to said discharge tip aboutthe periphery thereof, a gas supply line connected to said nozzle, acontrol valve in said line, a lineV branching from said first mentionedline at the discharge side of said valve and connected to said means,and pressure reducing means in said4 last mentioned line.

10. A burner comprising, in combination, a burner tube having a passageof which thedischarge end is flared convexly, the discharge tip of saidtube being peripherally unconiined and defining a fiat annular. endsurface merging with the outer peripheral margin oi the flared portionof said passage, means for supplying fuel to the discharge tip of saidtube at said surface, and means for supplying a stream of a fuel and airmixture at a relatively high velocity through said passage, said streamacting to induce a flow of supplemental air about the discharge tip ofsaid tube and a flow of fuel from said first mentioned means into saidstream.

11. A burner comprising, in combination, a`

body having an elongated discharge passage and a peripheral space, saidbody being formed with a plurality of peripherally spaced ports openingfrom said space about the outlet end of said passage, a casing on saidbody in communication with the inlet end of said passage, said casinghaving an air inlet, a shutter adjustably mounted on said casing forregulating the eiective opening of' said air inlet, a restricted nozzlein said casing for discharging axially into said passage, a highpressure fuel line connected to said nozzle, a regulating valve in saidline, and a supplemental line branching from said fuel line andconnected to said space.

, 12. A burner comprising, in combination, a body having an elongateddischarge passage and a peripheral space, said body being formed with aplurality of 'peripherally spaced ports opening from said .space aboutthe outlet end of said passage, a casing on said body in communicationwith the inlet end of said passage, said casing having an air inlet, ashutter adjustably mounted on said casing for regulating the effectiveopening of said air inlet, a restricted nozzle in said casing fordischarging axially into said passage, a high pressure fuel lineconnected to said nozzle, a regulating valve in said line, asupplemental line branching from said fuel line between said nozzle andsaid valve and connected to said space. and pressure reducing means insaid branch line, said air inlet when fully open not permitting theadmission of sumcient primary air to produce a combining air-fuel ratioin said passage.

GARNET W. MCKEE.

